The Maryland businessman has told authorities that Gardner disappeared in a snorkeling accident, but authorities say he has given inconsistent statements. Giordano also is said to be the beneficiary of a $1.5 million insurance policy on Gardner.

"There are some things we still need to confront him with," says Solicitor General Taco Stein, according to the Associated Press.

Andrea Colson, Gardner's mother, says in a statement she has "faith and confidence" in both Aruban authorities and the FBI and "know that they will fervently continue their efforts to find Robyn."

"This has been such a difficult time for all of us and your prayers have given us strength," says Colson. "We need to find our daughter."